Abstract Fragility is commonly quantified as the magnitude of change in viscosity at a temperature close to the glass transition temperature ( T g ). It is a critical characteristic of melts used in scientific and industrial applications. The fragility of silicate melts generally increases with the depolymerization of silicate anions upon the addition of alkali or alkaline earth oxides. However, the effects of oxide additives on the fragility of aluminosilicate melts remain unclear. In this study, the effect of CaO or K 2 O addition on the viscosity of the 36CaO–51SiO 2 –13Al 2 O 3 (mol.%) melt for the wide viscosity range of 10 −1 –10 12 Pa s was studied. The relationship between the logarithmic viscosity and T g ‐scaled temperature indicated that the melt fragility increased with the addition of CaO, whereas the addition of K 2 O reduced the fragility when the additive content of CaO or K 2 O was less than 10.8 mol.%. The effect of the addition of K 2 O on fragility cannot be explained by the depolymerization of silicate anions alone. Raman and 27 Al nuclear magnetic resonance spectroscopies of the glasses indicated that a decrease in the level of distortion of the AlO 4 tetrahedra decreased the fragility of the aluminosilicate melt.
The ideal periodontal treatment is regenerating functional periodontal tissues destroyed by severe periodontitis. The tissue engineering triad includes stem cells, biological signals, and cell-seeded scaffold that are considered to be essential for tissue regeneration. Periodontal ligament (PDL) tissue contains a stem cell population, periodontal ligament stem cells (PDLSC), that is derived the neural crest tissue. PDLSC demonstrate high proliferative capacity and multipotency that make them a highly promising stem cell population for use in the regeneration of damaged periodontal tissues.Here, we review the current understanding of the features and functions of PDLSC.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Abstract The authors previously described the design of shielded TM 010 dielectric rod resonators (below referred to as “TM 010 resonators”), a new configuration of small‐size resonators for microwave frequencies. This paper describes the design of bandpass filters using coaxially oriented electrically‐coupled TM 010 dielectric rod resonators. First, the resonant frequency of electrically‐coupled TM 010 resonators is analyzed by applying the Ritz‐Galerkin method to the integral equations that express the boundary conditions. This method is shown to be effective in numerical calculation of the coupling coefficients and center frequency of the coupled resonators and the resonant frequencies for inserted TM 010 resonators which are required for filter design. Next the characteristics of the coupling probe which effectively produces the strong coupling of the axially symmetric TM 010 mode of resonators and suppresses the excitation of the higher modes are determined experimentally, making it possible to estimate the center frequency for a filter which takes the variation of the resonant frequency produced by the excitation and coupling hole into consideration. Finally, design of 2‐ and 3‐stage filters of various bandwidths at 2.7 GHz demonstrates the suitability of the approach. Relative bandwidths of 1 to 10%, low losses of. 15 to. 6 db, and absence of spurious responses over bands wider than 1 octave are obtained.
Soccer is a high-intensity sport with a high injury rate. Among youth soccer players, lower extremity pain is a major problem that could be associated with trunk function. This study investigated the association between lower extremity pain and trunk pain among youth soccer players.A cross-sectional study involving youth soccer players participating in the Miyagi Amateur Sports Association was conducted using a self-reported questionnaire. A multiple logistic regression analysis was used to examine the association between trunk pain and lower extremity pain. Covariates were sex, age, body mass index, height increase, number of days of training per week, practice time per day on weekdays or weekends, competition levels, frequency of participation in games, and previous injuries.The final study population comprised 1139 youth soccer players (age, 6-15 years; male, 94.2%). Lower extremity pain with concomitant trunk pain occurred in 61.8% (42/68). Trunk pain was significantly associated with lower extremity pain (adjusted odds ratio [OR], 6.82; 95% confidence interval [CI], 3.99-11.67). Back pain and hip pain were significantly associated with knee pain (adjusted OR [95% CI]: 7.63 [3.70-15.76] and 3.84 [1.89-7.83], respectively), ankle pain (adjusted OR [95% CI]: 9.03 [4.42-18.44] and 5.43 [2.77-10.62], respectively), and both knee and ankle pain (adjusted OR [95% CI]: 13.67 [6.01-31.09] and 5.98 [2.56-13.97], respectively).Trunk pain was associated with lower extremity pain among youth soccer players. Clinicians and coaches should consider comorbidities while treating those players.
Abstract A one‐point back‐feed type circularly polarized microstrip disk antenna is investigated. To establish a design procedure, (1) the operating condition for circular polarization is studied and design formulas and data are presented and (2) the fabrication and radiation characteristics of arrays consisting of the present circularly polarized disk antenna element are discussed. It is demonstrated that this class of antennas can serve as a useful form of circularly polarized array element. Further, in order to analyze the mutual coupling of such antenna elements, the resonance and inter‐element mutual admittance of an array consisting of two disk antennas located on the same plane are determined. The fundamental information on the mutual coupling thus obtained is presented for a design aid. Using these results, a circularly polarized array is realized with good axial ratio and boresight ratio less than 0.5 dB.
Background: There is no established adequate treatment for thrombosed aneurysm of the basilar artery with obstructive hydrocephalus. We conducted coil embolization and peritoneal shunting followed by placement of a stent expected to exert flow diversion (FD) effects to treat 2 patients with giant thrombosed aneurysms of the basilar artery with associated obstructive hydrocephalus, with good results. Methods: From April 2019 to March 2021, consecutive two cases of symptomatic hydrocephalus due to giant thrombosed aneurysms in the posterior cranial fossa at our hospital were treated. At first, coil embolization was performed to prevent aneurysm rupture. After coil embolization, ventriculoperitoneal shunting was performed. Finally, stent-assisted coil embolization was performed with flow re-direction endoluminal device (FRED) or low-profile visualized intraluminal support device (LVIS) stent. Results: Both patients were discharged after recovering well, with no postoperative hemorrhagic or ischemic complications. Conclusion: Staged surgery using a FRED for flow diverter or an LVIS stent expected to have FD effects may offer an effective treatment option.
The aim of this study is to clarify the biological functions of decorin (DCN) in the healing and regeneration of wounded periodontal tissue. We investigated the expression pattern of DCN during the healing of wounded periodontal tissue in rats by immunohistochemistry and the effects of DCN on the osteoblastic differentiation of human periodontal ligament (PDL) stem cells (HPDLSCs) and preosteoblasts by Alizarin red S staining, quantitative reverse transcription-polymerase chain reactions, and western blotting. The expression of DCN was increased around the wounded PDL tissue on day 5 after surgery compared with the nonwounded PDL tissue, whereas its expression was not changed in the osteoblastic layer around the wounded alveolar bone. Furthermore, DCN promoted the osteoblastic differentiation of HPDLSCs, but it did not affect the osteoblastic differentiation of preosteoblasts. ERK1/2 phosphorylation was upregulated during the DCN-induced osteoblastic differentiation of HPDLSCs. DCN did not affect proliferation, migration, or the PDL-related gene expression of HPDLSCs. In conclusion, this study demonstrates that DCN has a role in the healing of wounded periodontal tissue. Furthermore, DCN secreted from PDL cells may contribute to bone healing by upregulating osteoblastic differentiation through ERK1/2 signaling in HPDLSCs, indicating a therapeutic effect of DCN in periodontal tissue regeneration.
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